Vibration isolation apparatus and methods of manufacture

Abstract

A vibration isolation apparatus is provided that includes a main spring and a tuned mass damper. The main spring has a first end and a second end, and is configured to resonate when vibrated within a predetermined frequency range with a first axial surge mode having a magnitude. The tuned mass damper is coupled to the main spring at a first axial position located substantially equidistantly between the main spring first end and the main spring second end and is configured to reduce the first axial surge mode magnitude at least 50% when the main spring is vibrated within the predetermined frequency range. Methods of manufacturing the vibration isolation apparatus are also provided.

1. A vibration isolation apparatus, comprising:
 a main spring having a first end and a second end, the main spring configured to resonate when vibrated within a predetermined frequency range with a first axial surge mode having a magnitude; and 
 a first pair of tuned mass dampers, each coupled to the main spring at a first axial position located substantially equidistantly between the main spring first end and the main spring second end, the first pair of tuned mass dampers spaced apart from each other substantially equidistantly around the main spring, and configured to reduce the first axial surge mode magnitude at least 50% when the main spring is vibrated within the predetermined frequency range. 
 
     
     
       2. The vibration isolation apparatus of  claim 1 , wherein the first pair of tuned mass dampers each includes a spring component and a mass disposed on the spring component. 
     
     
       3. The vibration isolation apparatus of  claim 2 , wherein the spring component is disposed substantially parallel with the main spring. 
     
     
       4. The vibration isolation apparatus of  claim 2 , wherein the first pair of tuned mass dampers each includes a housing within which the spring component is disposed and the housing is coupled to the main spring. 
     
     
       5. The vibration isolation apparatus of  claim 4 , wherein the first pair of tuned mass dampers each includes damping fluid disposed within the housing and surrounding the spring component. 
     
     
       6. The vibration isolation apparatus of  claim 1 , wherein the main spring has an outer surface and the tuned mass damper is coupled to the main spring outer surface. 
     
     
       7. The vibration isolation apparatus of  claim 1 , wherein the main spring has an inner surface and the first pair of tuned mass dampers is coupled to the main spring inner surface. 
     
     
       8. The vibration isolation apparatus of  claim 1 , wherein:
 the main spring is further configured to resonate with a second axial surge mode having a magnitude when vibrated within the predetermined frequency range; and 
 the vibration isolation apparatus further comprises a second pair of tuned mass dampers, each coupled to the main spring at a second axial position between the first axial position and the first main spring end and configured to reduce the second axial surge mode magnitude when the main spring is vibrated within the predetermined frequency range. 
 
     
     
       9. The vibration isolation apparatus of  claim 8 , wherein:
 the main spring is further configured to resonate with a third axial surge mode having a magnitude when vibrated within the predetermined frequency range; and 
 the vibration isolation apparatus further comprises a third pair of tuned mass dampers, each coupled to the main spring at a third axial position located between the first axial position and the second main spring end and configured to reduce the third axial surge mode magnitude when the main spring is vibrated within the predetermined frequency range. 
 
     
     
       10. A method of manufacturing a vibration isolation apparatus, the method comprising the steps of:
 coupling a pair of tuned mass dampers to a main spring at a first axial position located substantially equidistantly between a main spring first end and a main spring second end, 
 wherein the pair of tuned mass dampers are spaced apart from each other substantially equidistantly around the main spring, and are configured to reduce a first axial surge mode magnitude of the main spring at least 50% when the main spring is vibrated within a predetermined frequency range. 
 
     
     
       11. The method of  claim 10 , wherein the step of coupling comprises coupling the pair of tuned mass dampers to an outer surface of the main spring. 
     
     
       12. The method of  claim 10 , wherein the step of coupling comprises coupling the pair of tuned mass dampers to an inner surface of the main spring.